Roller pump



118-2 SEARCHROOM oEST AVAILABLE COPY United States Patent l1113,542,498

[72] inventor Harry .LSadler 3,381,622 5/1968 Wilcox 103/136X North St. Paul, Minnesota 3,402,672 9/1968 Cook ..103/136(A)UX p 761,479 Primary Examiner-William L. Freeh [22] Filed Sept. 23, 1968 [45] Patented Nov. 24, 1970 [73] Assignee Hypro, Inc.

St. Paul, Minnesota a corporation of Ohio Assistant Examiner-Warren J. Krauss Allorney-0rrin M. Haugen ABSTRACT: An improved roller pump having a rotor and a [54] ROLLER PUMP housing therefore, the axis of the rotor being offset from the 9 Claims Drawing Figs axis of the housing so as to form a pumping chamber therein,

the housing having porting formed along the end walls thereof [52] U.S.C| 418/225 so as to accommodate fluid flow metal-[rough The rotor is [51] lnt.Cl F04c l/00, Provided with roller receiving Skns having a Support base F04? 3/00FO4C 17/00 therein for limiting radial travel of the roller, along with a [50] Field of Search 103/136, depth extension thereof the deph extension continuing radi 136M); 230/152 ally inwardly and communicating directly with the openings to the porting. in addition. the rotor is provided with radially ex- [56] References cued tending reservoir channels disposed adjacent to the roller UNITED STATES PATENTS receiving slots, the reservoir channels being disposed so as to 2,460,018 1/1949 Looke ....l03/136(A)UX be in common communication with the port openings during a 2,725,013 11/1955 Vlachos... 103/136 substantial coincidental period of time with its adjacent roller 3,072,067 1/1963 Beller ..103/136(A)UX and roller receiving slot.

BEST AVAILABLE COPY Patent ed Nov. 24, 1970 3,542,498

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BEST AVAILABLE COPY Patented Nov. 24, 1970 3,542,498

29 f INVENTOR.

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BEST AVAILABLE COPY ROLLER PUMP The present invention relates generally to a rotary pump, and more specifically to a rotary pump of the type employing free-floating roller elements disposed in radially extending slots formed in a rotor element. The rotor is disposed within a pump housing, the housing having an axis which is offset from the axis of the rotor. Porting is provided in order to permit movement offluid through the pump.

In these rotary pumps, it has been customary to have ports arranged at arcuately spaced intervals about the pump, these ports ordinarily communicating with the roller receiving slot. In addition, the rotor has been provided with a number of radially extending slots, each slot being provided with a roller element therein. In the structure of the present invention, the roller receiving slots have a support plane substantially midway of its radial depth, and the portion below or radially inwardly from the roller is adapted to communicate directly with ports formed in the housing radially adjacent to the inwardly extending portions of the slot. In addition, additional reservoir volume is provided at a point adjacent the roller receiving slot, the reservoir area having a portion which is in direct communication with the porting.

In addition to these features, the porting has been arranged so as to geometrically accommodate the pump structure. In this connection, the inner radius ofthe port openings is coaxial with the axis of the housing, while the outer surface is arranged to be coaxial with the axis of the rotor. It has been found that the structure of the present invention provides a pump with a substantial degree of efficiency, with a capacity which varies only slightly with increases in vacuum, lift, or draw on the suction side. and with increases in pressure on the discharge side. The unit may be driven either directly from the shaft of an axially adjacent motor, or may be driven by means ofa pulley or other mechanical linkage, if desired.

Therefore, it is a primary object of the present invention to provide an improved roller pump structure having a rotor and a housing, the rotor being provided with a plurality of roller receiving slots, along with arcuately spaced and adjacent reservoir areas, the roller receiving slots having an inwardly extending portion which is adapted to communicate directly with axially and radially adjacent ports formed in the housing.

It is a further object of the present invention to provide an improved rotary pump having a rotor and a housing. the rotor being provided with a plurality of roller receiving slots, along with arcuately adjacent reservoir areas.

It is yet a further object of the present invention to provide an improved roller pump having a rotor with a plurality of radially extending roller receiving slots, each slot having a roller support surface substantially midway of its radial depth, along with an extension portion which lies radially inwardly of the support surface, the extension being in direct communication with arcuately arranged ports disposed along the housing area.

It is still a further object of the present invention to provide an improved roller pump having roller receiving slots with radially inwardly extending extensions, the housing for the rotor being provided with arcuately spaced inlet and outlet ports, the ports having an inner arcuate periphery which has a center coincident with the axis of the housing, the outer arcuate periphery of the porting having its center coinciding with the axis ofthe rotor.

Other and further objects of the present invention will become apparent to those skilled in the art upon a study of the following specification, appended claims. and accompanying drawings wherein:

FIG. 1 is an exploded perspective view of a pump structure prepared in accordance with a preferred modification of the present invention;

FIG. 2 is a plan view of the inner portion of the housing, this view being taken along the line and in the direction of the arrows 2-2 of FIG. 1;

FIG. 3 is a view similar to FIG. 2, showing the rotor structure of FIG. 6 confined within the housing;

FIG. 4 is a horizontal sectional view taken along the line and in the direction of the arrows 4-4 of FIG. 2',

FIG. 5 is a side elevational view, partially broken away, ofa modified form of pump utilizing a separate mechanical drive; and

FIG. 6 is a perspective view of a segment of a rotor formed in accordance with the present invention and utilizing a modified reservoir area.

In accordance with the preferred modification of the present invention, and with particular reference to FIG. 1 of the drawings, it will be observed that the pump generally designated 10 comprises a housing member 11 including an end plate portion 12 together with a cylindrical portion 13 forming a circumferential wall about a pumping chamber disposed therewithin. A rotor element 14 is provided which has a bore centrally thereof as at 16 for accommodating a shaft or the like in fast relationship thereto. The unit, including the housing 11 and rotor 14 are adapted to be clamped to the face 18 of the motor member 19, the shaft 20 being adapted to be received within the bore 16. Through bolts 21-21 are adapted to be utilized to clamp the member II on to the plate 18, with the O-ring groove 22 together with the enclosed ring 23 being utilized to seal the pumping chamber from the atmosphere. Also, as will be observed, key 25 is adapted to be received within the keyway formed in the shaft 20, and also within the keyway 26 of the rotor l4. Set screw 27 may be utilized, if desired, to assist in.retaining the rotor in fixed axial disposition on the shaft 20. As is indicated in the drawing, FIG. 1, the member II is provided with an inlet port 28, and an outlet 29, arcuate porting to the pumping chamber being provided internallyof the member I 1.

Particular attention is now directed to FIG. 2 of the drawings wherein the internal configuration ofthe member II is illustrated. The unit is provided with an arcuate inlet port 30 and an arcuate outlet port 31, each communicating internally with the inlet 28 and outlet 29, as illustrated, In addition, a relief port 32 is provided for reducing pressure on the shaft seal 34 disposed between the pumping chamber and the motor shaft, this bore communicating with the suction side of the pump drain 34a goes to atmosphere.

Turning now to the configuration of the rotor member 14, particularly as shown in FIG. 1 of the drawings, wherein this rotor is illustrated in detail. This rotor is provided with a plurality of roller receiving slots, such as the slot 35. the slot 35 having a roller supporting surface 36 disposed substantially midway between the outer circumference of the rotor and the inner extremity of the slot, such as at 37. In each of the roller receiving slots 35, a roller 38 is disposed for performing the function of this component in a pump of this type. Reference is made to U.S. Reissue Pat. No. RE 25.973, E. E. Cook, as signed to the Assignee of the present invention, for a detailed description ofthe operation ofpumps ofthis type.

Upon further study of the rotor 14, particularly as is illustrated in FIG. 1, it will be observed that additional slots are disposed arcuately adjacent the roller receiving slots 35, such as the slot shown at 40. This slot 40 functions as a reservoir zone, particularly in cooperation with the roller receiving slot 35 and its associated roller 38. The reservoir zone 40 is adapted to communicate with the inlet and outlet ports 30 and 31 respectively during a substantial portion of the arcuate travel of the slot 35 while adjacent or in communication with the respective ports. It will be further observed, upon a review of the geometry, that the roller supporting surface 36 limits the radial inward movement of the roller 38 during its travel, the depth of the slot to the surface 36 being substantially equal to the diameter of the roller 38. Below the roller receiving slot 35, an extension slot 37 is disposed, the outer periphery of the extension 37 coinciding with the roller supporting surface 36. Upon rotation of the rotor 14. the periphery of each of the ports, that is, the inlet and the outlet port, are disposed generally along the are generated by the roller supporting surface. Thus, the edge surfaces of the individual rollers 38 will not be in direct contact with the ports 30 and 31, but, on the other hand, communication will be established between the roller receiving slots 35-35 by virtue of their individual extensions 37-37. It will be observed that in the rotor 14, each of the roller receiving slots. the extensions thereof, the roller supporting surfaces. the rollers. as well as the reservoir zones are substantially identical, one to another. and for purposes of clarity specific reference will be made to only one of these QICQS- While the rotor is traveling about its rotational course, about its axis, the individual roller receiving slots 35 will communicate respectively with the inlet port 30, and thereafter with the outlet port 31. Upon communication being established with the inlet port 30, for example, the reservoir zone 40 will. for a substantial portion of the arcuate travel, be in common communication with the inlet port 30, coin cidentally with the roller receiving slot 35. Thus, the reservoir zone provides a fluid reservoir which can accommodate fiuid transfer between the roller receiving slots and the individual inlet and outlet ports respectively, these areas being in common communication, as previously indicated, with the individual ports. In order to avoid the effects ofcavitation, it has been found desirable to turn the radius of the reservoirs as at 4l. this providing for reduction or elimination of cavitation during operation.

Reference is made to FIGS. 3 and 6 ofthe drawings wherein a modified form of rotor is shown. This rotor. generally designated 50, comprises a body portion 51 having a roller receiving slot 52 formed therein. the slot 52 having a roller supporting surface 53 substantially midway of its depth. A roller member 54 is disposed within the slot, this roller having an axial dimension substantially equal to the axial width of the rotor member 50. At the base of the roller receiving slot 52, a channel zone is shown, such as at 55. this channel zone communicating with the radially extending relieved portions 56 and 57, an undercut beingprovided as at 58 in order to permit communication of fluid from one axial side to the other. As is indicated, the web of solid material as at 59 is provided to properly support the leading surface of the roller receiving slot 52, as at 60.

Particular attention is now directed to FIG. of the drawings wherein a pump generally designated 65 is illustrated, the pump structure and housing being substantially identical to that illustrated in FIGS. 1-4, and including, in addition thereto, a mounting bracket 66 for supporting the pump on a suitable surface, the unit further being provided with its own bearing as at 67, and seal as at 68. A pulley 69 is provided for rotating shaft 70, by means ofa remotely disposed motor or the like. It will be appreciated that other mechanical means may be utilized to establish or accommodate rotation of the shaft 70, as is conventional in units of this type.

The structural materials for the pump may include those conventionally utilized, such as cast iron or the like, and in the event unusual materials are being pumped, ceramic. plastic or other materials of construction may conveniently be employed. The roller materials may likewise be fabricated from desirable and compatible materials, consistent with the purpose for which the pump is being constructed, the suitable materials being, for example, cast iron, rubber-coated cast iron, and Teflon and the like.

It will be seen from a study of the structure that the unit is capable of an infinite variety of timing schedules, the timing schedules being appropriate for the specific use of the pump unit. For example, the inlet and outlet ports may have an arcuate dimension which will permit, is desired, only one of the roller receiving slots to be in communication at any given time. For certain other purposes, it may be desirable to permit coincidental communication with the inlet or outlet port by more than one roller receiving slot. it has been found that the structure of the present invention, particularly with the reservoir areas available, a high degree of efficiency in pumping capacity and operation is obtained, the reason for this efficiency being believed to be due to the lack of slippage or lost motion in the various parts and chambers. Furthermore, the provision of the roller supporting surface enhances the seal which is obtained between the inlet and outlet sides of the structure.

It will, of course, be understood that various forms of roller supporting surfaces, reservoir zones. and the like may be utilized, and those illustrated herein are for purposes of illustra tion only, and other forms will be found useful.

lclaim:

l. A roller pump comprising:

a. a housing having longitudinally spaced end walls and an intermediate circumferential wall forming a generally cylindrical pumping chamber;

b. a rotor rotatably mounted within said pumping chamber with its axis offset from that ofthe pumping chamber;

c. said rotor having a plurality of roller receiving slots formed into and across the circumferential surface thereofand uniformly angularly spaced therearound;

d. a cylindrical roller disposed in each roller receiving slot and having a length corresponding to the length of said roller receiving slot;

. an arcuate inlet port disposed in one of said end walls and an arcuate outlet port disposed in one ofsaid end wall; said roller receiving slot having a roller supporting surface spaced radially outwardly from the base thereof-and limiting the radial inward movement of a roller disposed within said slot; and

the radial outer periphery of each of said inlet and outlet ports being disposed generally along the are generated by said roller supporting surface upon rotation of said rotor within said housing so that said rollers do not extend radially inwardly of said outer peripheries.

2. The roller pump as defined in claim I being particularly characterized in that the inner periphery of each of said inlet and outlet ports is disposed generally along an arc having a center coincidental with the central axis of said intermediate circumferential wall.

3. A roller pump as defined in claim 1 being particularly characterized in that a radially extending slot is disposed arcuately immediately adjacent to each roller receiving slot, and communicates with the roller receiving slot through the inlet and outlet ports during each rotational cycle.

4. The roller pump as defined in claim 1 being particularly characterized in that a reservoir comprising a radial slot is formed adjacent to each roller receiving slot.

5. The roller pump as defined in claim 1 being particularly characterized in that said reservoir comprises a cavity formed in said rotor and communicating with an adjacent roller receiving slot at the base thereof.

6. The roller pump as defined in claim 1 being particularly characterized in that said roller receiving slot has a certain arcuate width. and is provided with a radially inwardly extending portion along a common radial axis.

7. The roller pump as defined in claim I being particularly characterized in that the arcuate length of the inlet port is substantially equal to the arcuate spacing of individual roller receiving slots and reservoir pairs.

8. The roller pump as defined in claim 1 being particularly characterized in that each of said inlet and outlet ports are formed in the same end wall.

9. A roller pump comprising:

a. a housing having longitudinally spaced end walls and an intermediate circumferential wall forming a generally cylindrical pumping chamber;

b. a rotor rotatably mounted within said pumping chamber with its axis offset from that of the pumping chamber;

c. said rotor having a plurality of roller receiving slots formed into and across the circumferential surface thereof and uniformly angularly spaced therearound;

d. a cylindrical roller disposed in each roller receiving slot and having a length corresponding to the length of said roller receiving slot;

e. an arcuate inlet port disposed in one of said end walls and an arcuate outlet port disposed in one of said end walls;

f. said roller receiving slot having a roller supporting surface spaced radially outwardly from the base thereof and limiting the radial inward movement of a roller disposed within said slot; and

BEST AVAILABLE COPY being substantially equal to the arcuate spacing of individual roller receiving slots and reservoir pairs, and the arcuate length of the outlet port being slightly less than that of the inlet port. 

